Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.

Patents

  1. Advanced Patent Search
Publication numberUS20040258040 A1
Publication typeApplication
Application numberUS 10/863,453
Publication date23 Dec 2004
Filing date7 Jun 2004
Priority date5 Jun 2003
Also published asUS7734809, WO2004109476A2, WO2004109476A3
Publication number10863453, 863453, US 2004/0258040 A1, US 2004/258040 A1, US 20040258040 A1, US 20040258040A1, US 2004258040 A1, US 2004258040A1, US-A1-20040258040, US-A1-2004258040, US2004/0258040A1, US2004/258040A1, US20040258040 A1, US20040258040A1, US2004258040 A1, US2004258040A1
InventorsAvinash Joshi, Surong Zeng, Guenael Strutt
Original AssigneeMeshnetworks, Inc.
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
System and method to maximize channel utilization in a multi-channel wireless communiction network
US 20040258040 A1
Abstract
A system and method for data transmission using a multichannel medium access control (MAC) protocol to send small messages on the reservation channel directly without any RTS/CTS handshake or channel switching delays. The message is assigned a special type so that it can be distinguished from the RTS/CTS message. The message can also include information about congestion, activity, device type, mobility level, and so forth.
Images(4)
Previous page
Next page
Claims(4)
What is claimed is:
1. A method for communicating between nodes in an ad-hoc multi-hopping peer-to-peer communication network, the method comprising:
tuning one of the nodes acting as a source node and another one of the nodes acting as a destination node to a reservation channel;
transmitting a short message from the source node to the destination node over the reservation channel without performing a request-to-send/clear-to-send handshake between the source and destination nodes.
2. A method as claimed in claim 1, wherein:
the short message is a hello message.
3. A method as claimed in clam 1, wherein:
the short message includes at least one of the following: information about congestion in the network around the source and destination nodes, information regarding activity of other nodes in the network, information pertaining to the device type of the source or destination node, and information pertaining to a mobility level of the source or destination node.
4. A method as claimed in claim 1, wherein:
the source and destination nodes are mobile nodes.
Description
  • [0001]
    This application claims benefit under 35 U.S.C. 119(e) from U.S. Provisional Patent Application Ser. No. 60/475,882, filed on Jun. 5, 2003, the entire content of which is incorporated herein by reference.
  • BACKGROUND OF THE INVENTION
  • [0002]
    1. Field of the Invention
  • [0003]
    The present invention relates to a system and method to increase channel utilization in a wireless communication network using a multichannel medium access control (MAC) protocol. The messages are sent directly on the reservation channel without any request-to-send/clear-to-send (RTS/CTS) handshake. Each message can further be assigned a special type indicator allowing it to be easily distinguished from the RTS/CTS message.
  • [0004]
    2. Description of the Related Art
  • [0005]
    Wireless communications networks, such as mobile wireless telephone networks, have become increasingly prevalent over the past decade. These wireless communications networks are commonly referred to as “cellular networks”, because the network infrastructure is arranged to divide the service area into a plurality of regions called “cells”. A terrestrial cellular network includes a plurality of interconnected base stations, or base nodes, that are distributed geographically at designated locations throughout the service area. Each base node includes one or more transceivers that are capable of transmitting and receiving electromagnetic signals, such as radio frequency (RF) communications signals, to and from mobile user nodes, such as wireless telephones, located within the coverage area. The communication signals may include, for example, voice data that has been modulated according to a desired modulation technique and transmitted as data packets. As can be appreciated by one skilled in the art, network nodes transmit and receive data packet communications in a multiplexed format, such as time-division multiple access (TDMA) format, code-division multiple access (CDMA) format, or frequency-division multiple access (FDMA) format, which enables a single transceiver at the base node to communicate simultaneously with several mobile nodes within its coverage area.
  • [0006]
    In recent years, a type of mobile communications network known as an “ad-hoc” network has been developed for use by the military. In this type of network, each mobile node is capable of operating as a base station or router for the other mobile nodes, thus eliminating the need for a fixed infrastructure of base stations. Details of an ad-hoc network are set forth in U.S. Pat. No. 5,943,322 to Mayor, the entire content of which is incorporated herein by reference.
  • [0007]
    More sophisticated ad-hoc networks are also being developed which, in addition to enabling mobile nodes to communicate with each other as in conventional ad-hoc networks, further enable mobile nodes to access a fixed network and thus communicate with other mobile nodes, such as those on the public switched telephone network (PSTN), and on other networks such as the Internet. Details of these advanced types of ad-hoc networks are described in U.S. Patent Application Ser. No. 09/897,790 entitled “Ad Hoc Peer-to-Peer Mobile Radio Access System Interfaced to the PSTN and Cellular Networks”, filed on Jun. 29, 2001, in U.S. patent application Ser. No. 09/815,157 entitled “Time Division Protocol for an Ad-Hoc, Peer-to-Peer Radio Network Having Coordinating Channel Access to Shared Parallel Data Channels with Separate Reservation Channel”, filed on Mar. 22, 2001, and in U.S. patent application Ser. No. 09/815,164 entitled “Prioritized-Routing for an Ad-Hoc, Peer-to-Peer, Mobile Radio Access System”, filed on Mar. 22, 2001, the entire content of each being incorporated herein by reference.
  • [0008]
    Communication between nodes in such networks, however, is often subject to collisions. One collision avoidance technique is carrier sense multiple access protocol (CSMA). In this technique, all nodes are forced to wait for a random number of timeslots and then sense the activity of the medium before starting a transmission. If the medium is sensed to be busy, the node freezes its timer until the medium becomes free again, thereby reducing the possibility of two nodes starting to send messages simultaneously. Therefore, as known to those skilled in the art, the range of the random delay, or the contention window, is set to vary with the load, and ARQ is used to finish the successful transmission process. After sending a packet, the sender waits for the “acknowledgement” (ACK) from the receiver. If ACK is not received within the specified time, the sender assumes that a collision has happened, and a retransmission is needed. In the case of a collision, the random delay range is increased progressively until a successful transmission occurs and the delay range is reset to the minimal value. In this case, the CSMA protocol handles ARQ by repeating the whole request to send/clear to send channel access sequence. Large delays are thus incurred due to retransmissions.
  • [0009]
    One problem associated with CSMA is that “carrier sense” only can detect the interference around the sender. However, of greater concern is interference at the receiver. In order to solve this problem, Phil Karn presented the Multiple Access with Collision Avoidance (MACA) protocol as described in the article entitled “MACA-A New Channel Access Method For Packet Radio”, the entire content of which is incorporated herein by reference. In MACA, a node requiring to transmit data to a receiver first sends a request-to-send (RTS) packet to the receiver to clear the sender's area. Upon receiving RTS successfully, the receiver responds with a clear-to-send (CTS) packet to clear the receiver's area. The RTS/CTS carries the information, which includes source/destination addresses, transmission duration, and so forth, for the intended transmission. Therefore, all nodes overhearing the RTS/CTS will hold their transmission long enough to avoid collision.
  • [0010]
    MACA protocol introduced RTS-CTS-DATA process to overcome the problem in CSMA. In order to accelerate the confirmation of the correct message transmission, the link layer ACK is introduced in MACAW proposed in “MACAW: A Media Access Protocol for Wireless LAN's” by V. Bharghavan et al., the entire content of which is incorporated herein by reference. One data transmission in MACAW includes RTS-CTS-DATA-ACK exchanges between the sender and the receiver. A variant of MACAW is used in IEEE 802.11 and is known as CSMA/CA. The multichannel MAC design is an extension of MACA/MACAW/CSMA/CA protocols. One channel is reserved for the transmission of control packets such as RTS, CTS, and other channels are used for data packet transmission. The typical process is described below.
  • [0011]
    In such a process, all nodes in the network keep listening to the reservation channel. Before data packet transmission, RTS/CTS are exchanged between the source and destination via the reservation channel. In RTS/CTS, besides the source/destination addresses and transmission duration information, the information of selected data channel is also carried. Once the exchange of RTS/CTS is successful, both sender and receiver tune to the selected data channel to transmit the data packet and ACK. Upon receiving the ACK, both sender and receiver retune back to the reservation channel to prepare for the future transmission. If a collision happens, the backoff process similar to which is in CSMA will be performed to resolve the collision.
  • [0012]
    In the multichannel MACA/MACAW and CSMA/CA protocols, the control packet overhead and the tuning delays between reservation channel and data channels are very high which reduces the channel utilization. This problem is more serious when the data packet size is very small. However, in order to coordinate nodes in Ad-Hoc networks, it is very important to distribute node information among neighbor nodes in the form of short Neighbor Advertisement (NA) or short “Hello” message. Accordingly, a need exists for minimizing the transmission overhead for small size packet in the multichannel MACA/MACAW or CSMA/CA protocol.
  • SUMMARY OF THE INVENTION
  • [0013]
    An object of the present invention is to provide a system and method for reducing delays in data transmissions using carrier sense multiple access with collision avoidance or a multiple access with collision avoidance as a medium access control protocol.
  • [0014]
    Another object of the present invention is to provide a system and method for detecting small unicast messages, and where possible, sending such messages directly on the reservation channel between nodes without any request-to-send/clear-to-send handshake.
  • [0015]
    Another object of the present invention is to provide a system and method for detecting small broadcast messages, and where possible, sending such messages directly on the reservation channel between nodes without any request-to-send message.
  • [0016]
    Still another object of the present invention is to provide a system and method for assigning a special type indicator to each small message allowing each to be easily distinguished from an RTS/CTS message.
  • [0017]
    Still another object of the present invention is to provide a system and method for sending each small message at constant power and data rates so such additional information does not need to be transmitted.
  • [0018]
    Still another object of the present invention is to provide a system and method for providing each small message with bits containing information about congestion, activity, device type, mobility level, and so forth.
  • [0019]
    These and other objects are substantially achieved by a system and method for data transmission using a carrier sense multiple access with collision avoidance or a multiple access with collision avoidance as a medium access control protocol to detect and send small messages without requiring the receiving node to switch to an indicated data channel. These messages are sent directly on the reservation channel without any request-to-send/clear-to-send handshake, and are assigned a special type indicator allowing each to be easily distinguished from an RTS/CTS message. Each message can be sent at constant power and data rate so such additional information does not need to be transmitted. Each message can also include, but is not limited to, bits containing information about congestion, activity, device type, mobility level, and so forth. Unlike standard practice, this allows creation of a unique MAC message which can be used to send short data messages directly on the reservation channel in a multi-channel MAC and avoid the delays associated with channel switching at both transmitting and receiving nodes.
  • BRIEF DESCRIPTION OF THE DRAWINGS
  • [0020]
    These and other objects, advantages and novel features of the invention will be more readily appreciated from the following detailed description when read in conjunction with the accompanying drawings, in which:
  • [0021]
    [0021]FIG. 1 is a block diagram of an example ad-hoc packet switched wireless communications network including a plurality of nodes in accordance with an embodiment of the present invention;
  • [0022]
    [0022]FIG. 2 is a block diagram illustrating an example of a mobile node employed in the network shown in FIG. 1;
  • [0023]
    [0023]FIG. 3A is a flow chart diagram illustrating a prior art short message communication; and
  • [0024]
    [0024]FIG. 3B is a flow chart diagram illustrating an implementation of an embodiment of the present invention in a short message communication.
  • DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
  • [0025]
    In the embodiment of the present invention described below, a data transmission system and method is described in which a MAC protocol is used to detect and send small messages on a reservation channel without requiring the receiving node to switch to an indicated data channel. These messages are sent directly on the reservation channel without any request-to-send/clear-to-send handshake, and associated channel switching delays.
  • [0026]
    As noted above, in a typical multi-channel wireless communication network using MACA/MACAW or CSMA/CA as MAC protocol, broadcast messages are sent on a data channel. Since all nodes of the network are assumed to constantly listen to the reservation channel, an RTS is sent which informs the neighboring nodes that the next message will be a broadcast message, and will be transmitted after a gap on channel x, where channel x can be any of the available channels in the multi-channel network. Upon receiving this RTS message, all nodes retune to channel x and receive the message. Each node then tunes back to the reservation channel. However, this series of communications results in the following delays. An RTS delay results from the time spent in sending/receiving the initial announcement about the broadcast. A GAP delay results from the time between the RTS and the broadcast message, which overlaps with the returning delay. A Message delay results from the time spent in sending/receiving the broadcast message, and a Return to Reservation Channel delay results from the time required to retune back to the reservation channel.
  • [0027]
    During the above delays, or “time slices”, no other transmissions can be made, as all the neighbor nodes need to listen to this broadcast packet. Also the nodes run into the risk of losing channel information and can cause hidden node problems which can result in packet collision and ultimately result in poor channel utilization. This process becomes increasingly more inefficient if the message sent on the data channel is comparable to the size of the RTS sent.
  • [0028]
    Therefore, if the message is small (i.e. comparable to the size of RTS message), the communication process becomes more efficient if the packet is sent on the reservation channel itself rather than the data channel. Such small messages include any number of communications, including a node “hello” or neighbor advertisement. Similarly, small unicast messages can also be sent directly on the reservation channel, thus avoiding RTS/CTS handshake overhead and tuning delays. Such messages can be exchanged in an illustrative network, such as the network 100 of FIG. 1.
  • [0029]
    [0029]FIG. 1 is a block diagram illustrating an example of an ad-hoc packet-switched wireless communications network 100 employing an embodiment of the present invention. Specifically, the network 100 includes a plurality of mobile wireless user terminals 102-1 through 102-n (referred to generally as nodes 102 or mobile nodes 102), and can, but is not required to, include a fixed network 104 having a plurality of access points 106-1, 106-2, . . . 106-n (referred to generally as nodes 106 or access points 106), for providing nodes 102 with access to the fixed network 104. The fixed network 104 can include, for example, a core local access network (LAN), and a plurality of servers and gateway routers to provide network nodes with access to other networks, such as other ad-hoc networks, the public switched telephone network (PSTN) and the Internet. The network 100 further can include a plurality of fixed routers 107-1 through 107-n (referred to generally as nodes 107 or routers 107) for routing data packets between other nodes 102, 106 or 107. It is noted that for purposes of this discussion, the nodes discussed above can be collectively referred to as “nodes 102, 106 and 107”, or simply “nodes”.
  • [0030]
    As can be appreciated by one skilled in the art, the nodes 102, 106 and 107 are capable of communicating with each other directly, or via one or more other nodes 102, 106 or 107 operating as a router or routers for packets being sent between nodes, as described in U.S. Pat. No. 5,943,322 to Mayor, and in U.S. patent application Ser. Nos. 09/897,790, 09/815,157 and 09/815,164, referenced above. As shown in FIG. 2, each node 102, 106 and 107 includes a transceiver 108 which is coupled to an antenna 110 and is capable of receiving and transmitting signals, such as packetized data, to and from the node 102, 106 or 107, under the control of a controller 112. The packetized data signals can include, for example, voice, data or multimedia information, and packetized control signals, including node update information.
  • [0031]
    Each node 102, 106 and 107 further includes a memory 114, such as a random access memory (RAM), that is capable of storing, among other things, routing information pertaining to itself and other nodes in the network 100. The nodes periodically exchange respective routing information, referred to as routing advertisements or routing table information, via a broadcasting mechanism, for example, when a new node enters the network or when existing nodes in the network move.
  • [0032]
    As further shown in FIG. 2, certain nodes, especially mobile nodes 102, can include a host 116 which may consist of any number of devices, such as a notebook computer terminal, mobile telephone unit, mobile data unit, or any other suitable device. Each node 102, 106 and 107 also includes the appropriate hardware and software to perform Internet Protocol (IP) and Address Resolution Protocol (ARP), the purposes of which can be readily appreciated by one skilled in the art. The appropriate hardware and software to perform transmission control protocol (TCP) and user datagram protocol (UDP) may also be included. Additionally, each node includes the appropriate hardware and software to perform automatic repeat request (ARQ) functions, carrier sense multiple access with collision avoidance (CSMA/CA) protocols, and multiple access with collision avoidance (MACA) protocols, and MACA for Wireless (MACAW) protocols as set forth in greater detail below.
  • [0033]
    In a typical network as shown in FIG. 1, regular neighbor advertisements are sent between nodes 102, 104, 106 and 107, on a regular interval to validate the bidirectional link between the sending node and its neighbor nodes. Such updated advertisements also assist in the quick convergence if a mobile node happens to visit the area. Since this neighbor advertisement message is typically sent by a Neighbor Discovery Module at each node 102, 106 and 107, which lies above the Link Layer in a typical architecture, it adds the LLC header and MAC layer header which increases the size of the packet.
  • [0034]
    However, to minimize the delays associated with the communication of such messages on the data channel, the embodiment of the present invention determines the size of the message, and where practical to do so, sends the message on the reservation channel. For these “hello” and other small messages, each can be sent on the reservation channel directly without any RTS/CTS handshake. In accordance with an embodiment of the present invention, the message can be assigned a special type or type indicator allowing it to be easily distinguished from an RTS/CTS message. Broadcast messages can furthermore be shortened as they do not require a destination address in addition to the source address. In this example, all hello messages can be treated as broadcast messages.
  • [0035]
    Each such message sent on the reservation channel can be sent at constant power and data rate levels, thereby eliminating the need to transmit this additional information. Each message can also include, but is not limited to, information about congestion, activity, device type, mobility level and so forth. Additionally, such messages can be helpful in providing smooth handoffs and continuous connectivity as described in U.S. Patent Application Ser. No. 60/439,449, entitled “System and Method for Achieving Continuous Connectivity to an Access Point or IAP or Gateway in a Network Following an On-Demand Routing Protocol” filed Jan. 13, 2003, and in U.S. Patent Application Ser. No. 60/439,455 entitled “System And Method For Modifying AODV To Facilitate Smooth Handoffs And Eliminate Unidirectional Links In A Wireless Network”, filed Jan. 13, 2003, in U.S. Provisional Patent Application Ser. No. 60/439,448, entitled “System and Method for Achieving Smooth Handoffs in Wireless Networks Using a Distance Vector Routing Algorithm”, filed Jan. 13, 2003, in U.S. patent application Ser. No. 10/755,346, entitled “System And Method For Achieving Continuous Connectivity To An Access Point Or Gateway In A Wireless Network Following An On-Demand Routing Protocol, and To Perform Smooth Handoff of Mobile Terminals Between Fixed Terminals in the Network”, filed Jan. 13, 2004, the entire content of each being incorporated herein by reference.
  • [0036]
    A flow chart representing the operation of the embodiment described above is shown in FIGS. 3A and 3B. FIG. 3A is a flow chart diagram illustrating a known short message communication technique. FIG. 3B is a flow chart diagram illustrating an implementation of an embodiment of the present invention in a short message communication between data terminals, such as nodes 102, 106 and 107.
  • [0037]
    In FIG. 3A, a first data terminal, or transmitting node sends an initial announcement about a broadcast at 122. A receiving node switches to an indicated data channel to receive the message at 124. The sending and receiving of this initial announcement results in a first time delay t1. The transmitting node then provides a gap at 126, during which the receiving node re-tunes to the proper data channel at 128, resulting in a second time delay t2. The broadcast message is sent at 130 and received at 132, resulting in a third time delay t3. The receiving node then returns to the reservation channel at 134, resulting in a fourth time delay t4. The cumulative time of the successful communication illustrated in FIG. 3A therefore is the sum of time delays t1-4.
  • [0038]
    In an embodiment of the present invention however shown in FIG. 3B, where messages are of a size less than or similar to an RTS message, a first data terminal, or transmitting node can send the message at 142 on the reservation channel. Therefore, the communication model shown in FIG. 3B includes merely time delay t1. The remaining delays of FIG. 3A have been eliminated.
  • [0039]
    The embodiment described above is highly efficient as nodes need not waste time in returning to different channels. Also, the embodiment mitigates hidden/exposed node problems as it increases the channel awareness among the nodes of the network.
  • [0040]
    Although only a few exemplary embodiments of the present invention have been described in detail above, those skilled in the art will readily appreciate that many modifications are possible in the exemplary embodiments without materially departing from the novel teachings and advantages of this invention. Accordingly, all such modifications are intended to be included within the scope of this invention.
Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US4617656 *2 Jan 198614 Oct 1986Tokyo Shibaura Denki Kabushiki KaishaInformation transmission system with modems coupled to a common communication medium
US4736371 *29 Dec 19865 Apr 1988Nec CorporationSatellite communications system with random multiple access and time slot reservation
US4742357 *17 Sep 19863 May 1988Rackley Ernie CStolen object location system
US4747130 *17 Dec 198524 May 1988American Telephone And Telegraph Company, At&T Bell LaboratoriesResource allocation in distributed control systems
US4910521 *3 Aug 198120 Mar 1990Texas Instruments IncorporatedDual band communication receiver
US5034961 *3 Jun 198823 Jul 1991Software Sciences LimitedArea communications system
US5068916 *29 Oct 199026 Nov 1991International Business Machines CorporationCoordination of wireless medium among a plurality of base stations
US5231634 *18 Dec 199127 Jul 1993Proxim, Inc.Medium access protocol for wireless lans
US5233604 *28 Apr 19923 Aug 1993International Business Machines CorporationMethods and apparatus for optimum path selection in packet transmission networks
US5241542 *23 Aug 199131 Aug 1993International Business Machines CorporationBattery efficient operation of scheduled access protocol
US5317566 *18 Aug 199331 May 1994Ascom Timeplex Trading AgLeast cost route selection in distributed digital communication networks
US5392450 *8 Jan 199221 Feb 1995General Electric CompanySatellite communications system
US5412654 *10 Jan 19942 May 1995International Business Machines CorporationHighly dynamic destination-sequenced destination vector routing for mobile computers
US5424747 *9 Apr 199313 Jun 1995Thomson-CsfProcess and system for determining the position and orientation of a vehicle, and applications
US5502722 *1 Aug 199426 Mar 1996Motorola, Inc.Method and apparatus for a radio system using variable transmission reservation
US5517491 *3 May 199514 May 1996Motorola, Inc.Method and apparatus for controlling frequency deviation of a portable transceiver
US5555540 *17 Feb 199510 Sep 1996Sun Microsystems, Inc.ASIC bus structure
US5572528 *20 Mar 19955 Nov 1996Novell, Inc.Mobile networking method and apparatus
US5615212 *11 Sep 199525 Mar 1997Motorola Inc.Method, device and router for providing a contention-based reservation mechanism within a mini-slotted dynamic entry polling slot supporting multiple service classes
US5618045 *8 Feb 19958 Apr 1997Kagan; MichaelInteractive multiple player game system and method of playing a game between at least two players
US5621732 *18 Apr 199515 Apr 1997Nec CorporationAccess method and a relay station and terminals thereof
US5623495 *15 Jun 199522 Apr 1997Lucent Technologies Inc.Portable base station architecture for an AD-HOC ATM lan
US5627976 *20 Mar 19956 May 1997Advanced Micro Devices, Inc.Crossing transfers for maximizing the effective bandwidth in a dual-bus architecture
US5631897 *1 Oct 199320 May 1997Nec America, Inc.Apparatus and method for incorporating a large number of destinations over circuit-switched wide area network connections
US5644576 *16 May 19951 Jul 1997International Business Machines CorporationMedium access control scheme for wireless LAN using a variable length interleaved time division frame
US5652751 *26 Mar 199629 Jul 1997Hazeltine CorporationArchitecture for mobile radio networks with dynamically changing topology using virtual subnets
US5680392 *16 Jan 199621 Oct 1997General Datacomm, Inc.Multimedia multipoint telecommunications reservation systems
US5684794 *25 Jan 19964 Nov 1997Hazeltine CorporationValidation of subscriber signals in a cellular radio network
US5687194 *22 Apr 199311 Nov 1997Interdigital Technology CorporationSubscriber RF telephone system for providing multiple speech and/or data signals simultaneously over either a single or a plurality of RF channels
US5706428 *14 Mar 19966 Jan 1998Lucent Technologies Inc.Multirate wireless data communication system
US5717689 *10 Oct 199510 Feb 1998Lucent Technologies Inc.Data link layer protocol for transport of ATM cells over a wireless link
US5745483 *29 Sep 199528 Apr 1998Ricoh Company, Ltd.Wireless computer network communication system and method having at least two groups of wireless terminals
US5774876 *26 Jun 199630 Jun 1998Par Government Systems CorporationManaging assets with active electronic tags
US5781540 *30 Jun 199514 Jul 1998Hughes ElectronicsDevice and method for communicating in a mobile satellite system
US5787080 *3 Jun 199628 Jul 1998Philips Electronics North America CorporationMethod and apparatus for reservation-based wireless-ATM local area network
US5794154 *26 Jul 199611 Aug 1998Motorola, Inc.Communications system and method of operation
US5796732 *28 Mar 199618 Aug 1998Cisco Technology, Inc.Architecture for an expandable transaction-based switching bus
US5796741 *5 Mar 199618 Aug 1998Nippon Telegraph And Telephone CorporationATM bus system
US5805593 *26 Sep 19958 Sep 1998At&T CorpRouting method for setting up a service between an origination node and a destination node in a connection-communications network
US5805842 *26 Sep 19958 Sep 1998Intel CorporationApparatus, system and method for supporting DMA transfers on a multiplexed bus
US5805977 *1 Apr 19968 Sep 1998Motorola, Inc.Method and apparatus for controlling transmissions in a two-way selective call communication system
US5809518 *20 May 199615 Sep 1998Dallas Semiconductor CorporationCommand/data transfer protocol for one-wire-bus architecture
US5822309 *15 Jun 199513 Oct 1998Lucent Technologies Inc.Signaling and control architecture for an ad-hoc ATM LAN
US5857084 *2 Oct 19965 Jan 1999Klein; Dean A.Hierarchical bus structure access system
US5870350 *21 May 19979 Feb 1999International Business Machines CorporationHigh performance, high bandwidth memory bus architecture utilizing SDRAMs
US5877724 *25 Mar 19972 Mar 1999Trimble Navigation LimitedCombined position locating and cellular telephone system with a single shared microprocessor
US5881095 *1 May 19979 Mar 1999Motorola, Inc.Repeater assisted channel hopping system and method therefor
US5881372 *1 Dec 19959 Mar 1999Lucent Technologies Inc.Radio communication device and method
US5886992 *15 Apr 199723 Mar 1999Valtion Teknillinen TutkimuskeskusFrame synchronized ring system and method
US5896561 *23 Dec 199620 Apr 1999Intermec Ip Corp.Communication network having a dormant polling protocol
US5903559 *20 Dec 199611 May 1999Nec Usa, Inc.Method for internet protocol switching over fast ATM cell transport
US5909651 *5 May 19971 Jun 1999Lucent Technologies Inc.Broadcast short message service architecture
US5936953 *18 Dec 199710 Aug 1999Raytheon CompanyMulti-mode, multi-channel communication bus
US5943322 *24 Apr 199624 Aug 1999Itt Defense, Inc.Communications method for a code division multiple access system without a base station
US6028853 *6 Jun 199722 Feb 2000Telefonaktiebolaget Lm EricssonMethod and arrangement for radio communication
US6029217 *3 Oct 199422 Feb 2000International Business Machines CorporationQueued arbitration mechanism for data processing system
US6034542 *14 Oct 19977 Mar 2000Xilinx, Inc.Bus structure for modularized chip with FPGA modules
US6044062 *6 Dec 199628 Mar 2000Communique, LlcWireless network system and method for providing same
US6047330 *20 Jan 19984 Apr 2000Netscape Communications CorporationVirtual router discovery system
US6052594 *30 Apr 199718 Apr 2000At&T Corp.System and method for dynamically assigning channels for wireless packet communications
US6052752 *14 Nov 199618 Apr 2000Daewoo Telecom Ltd.Hierarchical dual bus architecture for use in an electronic switching system employing a distributed control architecture
US6064626 *31 Jul 199816 May 2000Arm LimitedPeripheral buses for integrated circuit
US6067291 *23 Sep 199723 May 2000Lucent Technologies Inc.Wireless local area network with enhanced carrier sense provision
US6067297 *28 Jun 199623 May 2000Symbol Technologies, Inc.Embedded access point supporting communication with mobile unit operating in power-saving mode
US6078566 *28 Apr 199820 Jun 2000Genesys Telecommunications Laboratories, Inc.Noise reduction techniques and apparatus for enhancing wireless data network telephony
US6104712 *22 Feb 199915 Aug 2000Robert; Bruno G.Wireless communication network including plural migratory access nodes
US6108738 *10 Jun 199722 Aug 2000Vlsi Technology, Inc.Multi-master PCI bus system within a single integrated circuit
US6115580 *8 Sep 19985 Sep 2000Motorola, Inc.Communications network having adaptive network link optimization using wireless terrain awareness and method for use therein
US6122690 *17 Apr 199819 Sep 2000Mentor Graphics CorporationOn-chip bus architecture that is both processor independent and scalable
US6130881 *20 Apr 199810 Oct 2000Sarnoff CorporationTraffic routing in small wireless data networks
US6132306 *29 Mar 199617 Oct 2000Cisco Systems, Inc.Cellular communication system with dedicated repeater channels
US6178337 *19 Jun 199723 Jan 2001Qualcomm IncorporatedWireless telecommunications system utilizing CDMA radio frequency signal modulation in conjuction with the GSM A-interface telecommunications network protocol
US6192053 *7 Sep 199520 Feb 2001Wireless Networks, Inc.Enhanced adjacency detection protocol for wireless applications
US6192230 *27 Sep 199320 Feb 2001Lucent Technologies, Inc.Wireless data communication system having power saving function
US6208870 *1 Jun 199927 Mar 2001Lucent Technologies Inc.Short message service notification forwarded between multiple short message service centers
US6222463 *25 Jun 199824 Apr 2001Lucent Technologies, Inc.Vehicle communication network
US6222504 *14 Jan 200024 Apr 2001Omnipoint CorporationAdjustable antenna mount with rotatable antenna brackets for PCS and other antennas
US6223240 *31 Jan 200024 Apr 2001Lsi Logic CorporationBus bridge architecture for a data processing system capable of sharing processing load among a plurality of devices
US6240083 *25 Feb 199729 May 2001Telefonaktiebolaget L.M. EricssonMultiple access communication network with combined contention and reservation mode access
US6240294 *30 May 199729 May 2001Itt Manufacturing Enterprises, Inc.Mobile radio device having adaptive position transmitting capabilities
US6246875 *26 Mar 199912 Jun 2001Bell Atlantic Network Services, Inc.Use of cellular digital packet data (CDPD) communications to convey system identification list data to roaming cellular subscriber stations
US6249516 *27 Jan 200019 Jun 2001Edwin B. BrownriggWireless network gateway and method for providing same
US6275707 *8 Oct 199914 Aug 2001Motorola, Inc.Method and apparatus for assigning location estimates from a first transceiver to a second transceiver
US6285892 *24 Nov 19984 Sep 2001Philips Electronics North America Corp.Data transmission system for reducing terminal power consumption in a wireless network
US6304556 *24 Aug 199816 Oct 2001Cornell Research Foundation, Inc.Routing and mobility management protocols for ad-hoc networks
US6349091 *7 Nov 200019 Feb 2002Itt Manufacturing Enterprises, Inc.Method and apparatus for controlling communication links between network nodes to reduce communication protocol overhead traffic
US6349210 *3 Nov 200019 Feb 2002Itt Manufacturing Enterprises, Inc.Method and apparatus for broadcasting messages in channel reservation communication systems
US6359872 *28 Oct 199719 Mar 2002Intermec Ip Corp.Wireless personal local area network
US6366568 *4 Oct 19952 Apr 2002Interdigital Technology CorporationTransfer station for wireless telephone distribution system with time and space diversity transmission
US6400726 *24 Dec 19974 Jun 2002Canon Kabushiki KaishaAllocation to a plurality of elements of authorizations for access to a shared resource
US6405049 *5 Aug 199711 Jun 2002Symbol Technologies, Inc.Portable data terminal and cradle
US6526027 *21 Dec 199825 Feb 2003Lg Information & Communications, Ltd.Broadcast short message service execution method in a mobile communication system
US6807165 *22 Mar 200119 Oct 2004Meshnetworks, Inc.Time division protocol for an ad-hoc, peer-to-peer radio network having coordinating channel access to shared parallel data channels with separate reservation channel
US6873839 *22 Mar 200129 Mar 2005Meshnetworks, Inc.Prioritized-routing for an ad-hoc, peer-to-peer, mobile radio access system
US7072650 *29 Jun 20014 Jul 2006Meshnetworks, Inc.Ad hoc peer-to-peer mobile radio access system interfaced to the PSTN and cellular networks
US7130282 *20 Sep 200231 Oct 2006Qualcomm IncCommunication device for providing multimedia in a group communication network
US20020013856 *21 Sep 200131 Jan 2002Garcia-Luna-Aceves J. JoaquinUnified routing scheme for ad-hoc Internetworking
US20030179741 *5 Feb 200225 Sep 2003Force 10 Networks, Inc.High-speed router with single backplane distributing both power and signaling
US20040143842 *13 Jan 200422 Jul 2004Avinash JoshiSystem and method for achieving continuous connectivity to an access point or gateway in a wireless network following an on-demand routing protocol, and to perform smooth handoff of mobile terminals between fixed terminals in the network
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US772008619 Mar 200718 May 2010Microsoft CorporationDistributed overlay multi-channel media access control for wireless ad hoc networks
US7734809 *7 Jun 20048 Jun 2010Meshnetworks, Inc.System and method to maximize channel utilization in a multi-channel wireless communication network
US839608630 Sep 200912 Mar 2013Google Inc.Scalable association scheme for TV white-space MIMO wireless system
US855945530 Sep 200915 Oct 2013Google Inc.Dynamic scheduling scheme for TV white-space MIMO wireless system
US856513830 Sep 200922 Oct 2013Google Inc.Random shuffling mechanism for MIMO wireless system
US869404213 Oct 20068 Apr 2014Qualcomm IncorporatedMethod and apparatus for determining a base station's transmission power budget
US869941130 Sep 200915 Apr 2014Google Inc.Dynamic TDMA system for TV white space MIMO wireless
US8811345 *7 May 201019 Aug 2014Qualcomm IncorporatedMethod and apparatus for facilitating user equipment backoff during random access procedures
US881134817 Jan 200619 Aug 2014Qualcomm IncorporatedMethods and apparatus for generating, communicating, and/or using information relating to self-noise
US883082714 Sep 20129 Sep 2014Qualcomm IncorporatedMethods and apparatus for communicating transmission backlog information
US89654134 Mar 201124 Feb 2015Qualcomm IncorporatedLocating a wireless local area network associated with a wireless wide area network
US898908413 Oct 200624 Mar 2015Qualcomm IncorporatedMethods and apparatus for broadcasting loading information corresponding to neighboring base stations
US911922013 Dec 200625 Aug 2015Qualcomm IncorporatedMethods and apparatus for communicating backlog related information
US912509214 Jul 20061 Sep 2015Qualcomm IncorporatedMethods and apparatus for reporting and/or using control information
US912509313 Oct 20061 Sep 2015Qualcomm IncorporatedMethods and apparatus related to custom control channel reporting formats
US913707214 Jul 200615 Sep 2015Qualcomm IncorporatedMethods and apparatus for communicating control information
US914879517 Jan 200629 Sep 2015Qualcomm IncorporatedMethods and apparatus for flexible reporting of control information
US916131317 Oct 201213 Oct 2015Qualcomm IncorporatedMethods and apparatus for communicating and/or using transmission power information
US9191828 *28 Nov 201217 Nov 2015Intel CorporationHigh efficiency distributed device-to-device (D2D) channel access
US919184014 Jul 200617 Nov 2015Qualcomm IncorporatedMethods and apparatus for determining, communicating and using information which can be used for interference control
US933876717 Jan 200610 May 2016Qualcomm IncorporatedMethods and apparatus of implementing and/or using a dedicated control channel
US933879512 May 201010 May 2016Qualcomm IncorporatedMethods and apparatus for communicating transmission backlog information
US93637022 Aug 20137 Jun 2016Intel CorporationMethod and system for enabling device-to-device communication
US937478315 Dec 201421 Jun 2016Intel CorporationEnhanced node B, user equipment and methods for discontinuous reception in inter-eNB carrier aggregation
US945149117 Jan 200620 Sep 2016Qualcomm IncorporatedMethods and apparatus relating to generating and transmitting initial and additional control information report sets in a wireless system
US945643417 Mar 201427 Sep 2016Google Inc.Dynamic TDMA system for TV white space MIMO wireless
US946260412 Dec 20064 Oct 2016Qualcomm IncorporatedMethods and apparatus related to selecting a request group for a request report
US947326514 Jul 200618 Oct 2016Qualcomm IncorporatedMethods and apparatus for communicating information utilizing a plurality of dictionaries
US954486025 Aug 200310 Jan 2017Qualcomm IncorporatedPilot signals for use in multi-sector cells
US95542962 Aug 201324 Jan 2017Intel CorporationDevice trigger recall/replace feature for 3GPP/M2M systems
US957217914 Jul 200614 Feb 2017Qualcomm IncorporatedMethods and apparatus for communicating transmission backlog information
US957865413 Dec 200621 Feb 2017Qualcomm IncorporatedMethods and apparatus related to selecting reporting alternative in a request report
US960310214 May 200721 Mar 2017Qualcomm IncorporatedMethod of transmitting pilot tones in a multi-sector cell, including null pilot tones, for generating channel quality indicators
US966151914 Jul 200623 May 2017Qualcomm IncorporatedEfficient reporting of information in a wireless communication system
US96868178 Jun 201620 Jun 2017Intel CorporationApparatus of user equipment (UE) configurable for connectivity with multiple cell groups
US9713169 *3 Apr 201518 Jul 2017Spreadtrum Communications (Shanghai) Co., Ltd.Method and apparatus for controlling startup of request to send/clear to send mechanism
US20060007882 *7 Jul 200512 Jan 2006Meshnetworks, Inc.System and method for selecting stable routes in wireless networks
US20070223427 *27 Jun 200627 Sep 2007Fujitsu LimitedBase station apparatus, terminal, and bandwidth control method
US20070253449 *8 Dec 20061 Nov 2007Arnab DasMethods and apparatus related to determining, communicating, and/or using delay information
US20070286139 *6 Feb 200713 Dec 2007Lucent Technologies Inc.Methods of routing data within a wireless communication system
US20080232389 *19 Mar 200725 Sep 2008Microsoft CorporationDistributed Overlay Multi-Channel Media Access Control for Wireless Ad Hoc Networks
US20090138602 *27 Nov 200728 May 2009James Paul SchneiderSecured agent communications
US20100214945 *6 May 201026 Aug 2010Microsoft CorporationDistributed Overlay Multi-Channel Media Access Control (MAC) for Wireless Ad Hoc Networks
US20120275429 *7 May 20101 Nov 2012Qualcomm IncorporatedMethod and Apparatus for Facilitating User Equipment Backoff During Random Access Procedures
US20140036876 *28 Nov 20126 Feb 2014Honggang LiHigh efficiency distributed device-to-device (d2d) channel access
US20160037502 *3 Apr 20154 Feb 2016Spreadtrum Communications (Shanghai) Co., Ltd.Method and apparatus for controlling startup of request to send/clear to send mechanism
WO2004064303A213 Jan 200429 Jul 2004Meshnetworks, Inc.Method for continuous connectivity to an access point in a wireless network
WO2017112338A1 *25 Nov 201629 Jun 2017Intel CorporationCongestion management techniques for communication networks
Classifications
U.S. Classification370/349
International ClassificationG06F, H04L1/00
Cooperative ClassificationH04W4/14
European ClassificationH04W4/14
Legal Events
DateCodeEventDescription
7 Jun 2004ASAssignment
Owner name: MESHNETWORKS, INC., FLORIDA
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:JOSHI, AVINASH;ZENG, SURONG;STRUTT, GUENAEL;REEL/FRAME:015458/0080
Effective date: 20040607
Owner name: MESHNETWORKS, INC.,FLORIDA
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:JOSHI, AVINASH;ZENG, SURONG;STRUTT, GUENAEL;REEL/FRAME:015458/0080
Effective date: 20040607
24 Jul 2012CCCertificate of correction
26 Nov 2013FPAYFee payment
Year of fee payment: 4